Sequencing valve

ABSTRACT

A flow sequencing valve which employs separate valve elements to generate the force required for cycling and to accomplish discharge port sealing is disclosed. The valve may include an integral pilot solenoid for controlling cycling and is characterized by a force generating element, in the form of a variable resistance to flow, which is free to overtravel relative to the port sealing member whereby flow rate compensation is achieved and water hammer effects eliminated.

United States atent [1 1 m1 3,75,391 Miller 1 Jan. 15, 1974 1 SEQUENCHNGVALVE Bob C. Miller, 272 River Dr., Tequesta, Fla. 33458 Filed: Jan. 16,1973 Appl. No.: 324,236

lnventor:

U.S. Cl 137/119, 137/624.l4, 137/625.1l Int. Cl. FltSk 21/011 Field ofSearch 137/119, 624.14,

References Cited UNITED STATES PATENTS 2/1968 Haggard 137/625.11

3/1969 Tidd 1 1 137/119 l/l972 Kah 137/119 Primary ExaminerRobert G.Nilson Assistant ExaminerEdward Look Attorney-David S. Fishman et a1.

[57] ABSTRACT 17 Claims, 5 Drawing Figures PATENTEU 1 5'974 3,735,391

' sum 1 Of a 1 SEQUENCING VALVE BACKGROUND OF THE INVENTION l. Field ofthe Invention The present invention relates to fluid handling andparticularly to the delivery of fluid from a source to a plurality offluid consuming loads in a predetermined sequence. More specifically,this invention is directed to distributing valves operable tosequentially deliver a fluid under pressure from a source to one or moredischarge or distribution lines. Accordingly, the general objects of thepresent invention are to provide novel and improved methods andapparatus of such character.

2. Description of the Prior Art While not limited thereto in theirutility, fluid control devices of the general type to which the presentinvention relates have been found to be particularly useful inirrigation systems. In such systems it is often desired to supply waterfrom a single source in sequence to a number of distribution lines; eachof the distribution lines typically including a plurality of sprinklerheads. Such systems require at least one sequential distributing valvewhich is operable to connect the source to the distribution lines in apredetermined sequence; the distribution lines typically being suppliedin individual fashion.

Sequencing valves for use in the above briefly described irrigationsystems, as well as in numerous other environments, are well known inthe art. However, as will be described briefly below, all previouslyavailable sequencing valves have been characterized by a number ofinherent operational deficiencies. Certain of these deficiencies havecharacterized the sequencing valves designed in accordance with each ofthe several technical approaches to providing flow switching whichhave'been followedf As noted immediately above, prior art sequencingvalves have embodied a number of different technical approaches. Thus,by way of example, a plurality of electrically or hydraulically operatedremotely controlled valves have been proposed and in some casesutilized. As employed in this brief discussion of the prior art, aremotely hydraulically controlled valve is a device which is operated inresponse to a control signal delivered via a hydraulic line which isseparate from the main fluid flow path or via an electrical cable. Whilepossessed of a number of other significant disadvantages, the remotelyoperated valves of the prior art also share two principal deficiencieswith all other prior art sequencing valves. These deficiencies areexcessive system cost due to the necessity of employing a plurality ofvalves and a corresponding lack of system reliability resulting from thecomparatively large total number of moving parts employed in a system.

Another approach to the design of a successful sequencing valve has beenembodied in solenoid operated devices. Although directly operatedsolenoid controlled sequencing valves have been proposed, such valveshave not been used extensively due to their high cost, limited utilityand lack of reliability. Thus, by way of example, direct operatedsolenoid controlled sequencing valves are not suitable for use with acompletely automatic pump fed distribution system unless a separatetimer is employed to turn on the pump. Solenoid controlled directlyoperated sequencing valves are -meter operated valves also require asingle station timer for fully automatic operation and such valves arecharacterized by a relatively high pressure loss. Additionally, flowmeter operated valves are overly complex and subject to contaminationdamage.

The technical approach to sequencing valve design which has resulted inthe prior art devices which have achieved the widest acceptancecontemplates that the valve discharge port switching function becontrolled by pulsing the flow from the fluid source. Such flow operatedsequencing valves have employed ball-type .valves, as exemplified by H.Davis U.S. Pat. No.

3,472,265, and rotary-axially movable valve elements, as exemplified bythe cam operated device of E. Haggard U.S. Pat. No. 3,369,565. While theHaggard patent discloses a sequencing valve having an integrally mountedsolenoid operated pilot valve, it will be obvious to those skilled inthe art that the sequencing valve of U.S. Pat. No. 3,369,565 can operatein response to supply fluid pulses delivered to the valve inlet as aresult of the operation of a suitable control device located at thesource of the fluid to be distributed.

As noted above, all previous flow operated sequencing valves have beencharacterized by several inherent deficiencies. Perhaps the mostsignificant of these deficiencies has been an inability of the prior artdevices to operate over a wide flow range; this deficiency preventingthe adaptation ofa single valve to a variety of applications. Theinability to operate over a wide flow range has typically been evidencedas a failure of the valve to cycle at low flow rates. There have been anumber of attempts made to provide a sequencing valve which are cycle atlow flow rates. The prior attempts to obtain low flow rate cycling areexemplified by the valve disclosed in U.S. Pat. No. 3,524,470 to C. Kah,Jr. The device of U.S. Pat. No. 3,524,470 incorporates flap valves inthe valving member and, while this technique reduces the flow requiredto cycle, thus inherently offers substantial area for leakage around thevalving member which establishes the minimum flow rate required tocycle. Additionally, the valve of U.S. Pat. No. 3,524,470. exhibits anarrow operational flow range if a unreasonable pressure loss is to bemaintained.

Thus, to summarize the above, in previously available flow operatedsequencing valves, significant flow has been required for valveoperation since the pressure drop across'the valve element is used togenerate the force required for cycling. Obviously, if a reasonablepressure drop at high flowrates is to be maintained, a large port areain the valve element must be provided and the flow rate through thisport area and around the outer diameter of the valve element must besignificant to generate an adequatepressure differential to achievecycling. Accordingly, prior art flow operated sequencing valves havebeen characterized by a compromise between a high pressure drop and anextremely large valve structure.

The second most significant deficiency of all prior art sequencingvalves, including those briefly discussed above, is the water hammereffect created as the valves are cycled. The possible detrimentaleffects of water hammer to the valve itself and other components of thefluid distribution sytem are well known and will not be discussedherein. Water hammer has resulted because, prior to complete cycling,all of the outlet ports are exposed to the inlet thereby providing verylow resistance to flow and consequently a high flow rate. When the valveelement is seated the resistance to flow is reduced to that of a singleflow circuit and the total flow is suddenly reduced thus producing waterhammer.

A further disadvantage of prior art flow operated sequencing valvesresides in the susceptability of the previous devices to jamming failureresulting from contamination. In many installations sand or othercontaminates may enter the system and these contaminates may wedgebetween close fitting parts, such as the valving member and housing,thereby causing improper operation; this being a particular problem inthe typical prior art device wherein such close fitting parts areexposed to the flow stream through the sequencing valve. The lack ofreliability of prior art flow operated sequencing valves resulting fromtheir susceptability to contamination has been aggravated by the factthat the devices have employed a comparatively large number of movingparts. Prior art flow operated sequencing valves have been furthercharacterized by delay in or failure to cycle as a result of back flowfrom elevated outlet circuits. The typical prior art solution to theback flow problem has been to incorporate check valves in the elevatedcircuits and this, of course, has added to the expense and complexity ofthe entire distribution system.

SUMMARY OF THE INVENTION The present invention overcomes the abovediscussed and other deficiencies and disadvantages of the prior art bypro-viding a flow compensated sequencing valve wherein separate valveelements are employed to generate the force required for cycling and toaccomplish discharge port sealing and switching. In accordance with apreferred embodiment, the force generating element is a pintle memberwhich cooperates with an inlet port defining member to define a variablyrestricted flow path and thus to generate adequate forces for cyclingeven at low flow rates. The pintle member is resiliently coupled to andthus free to over-travel relative to the valve rotor, which functions asthe discharge port sealing member, and low pressure losses at high flowrates are accordingly achieved. Since a pressure drop across the portsealing member is not required for cycling, valves in accordance withthe present invention may incorporate large low pressure loss dischargeports and are characterized by a large clearance between the portsealing member and valve housing whereby a high degree of contaminationinsensitivity is achieved.

Also in accordance with the preferred embodiment of the invention, theelements which provide for the indexing of the valve sealing member arelocated in such a manner as to be isolated from exposure to anycontaminates which may be carried by the fluid being distributed.Further, a conical rotor configuration directs any contaminates enteringthe valve to the open discharge port in the preferred embodiment thusproviding a self-cleaning feature while permitting a smooth transitionfrom the valve exit port to the discharge fitting.

In addition to contamination insensitivity and an independent variablerestriction, as defined by the pintle member, sequencing valves inaccordance with the present invention may include a solenoid operatedpilot valve. When the the pilot valve subassembly is included it willcomprise a flexible diaphragm and the actual pilot valve will controlthe invention of a diaphragm chamber whereby the pressure across andthus the movements of the diaphragm are controllable. Movements of thediaphragm are coupled to the pintle either directly mechanically orfluidically in the interest of sufficiently decreasing the pressuredifferential across the pintle to permit cycling.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be betterunderstood and its numerous objects and advantages will become apparentto those skilled in the art by reference to the accompanying drawingwherein like reference numerals refer to like elements in the severalfigures and in which:

FIG. 1 is a cross-sectional, side elevation view of a first embodimentof a flow operated sequencing valve in accordance with the presentinvention, the embodiment of FIG. 1 including an integral solenoidoperated pilot valve;

FIGS. 2 and 2A are schematic views depicting two of the severalalternate outlet port configurations which may be employed in the valveof FIG. 1;

FIG. 3 is a linear representation of the cylindrical cam mechanism ofthe valve of FIG. 1; and

FIG. 4 is a cross-sectional, side elevation view of a second embodimentof a valve in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS:

With reference now to FIG. 1, a flow compensated sequencing valve inaccordance with the present invention comprises a housing indicatedgenerally at 10. Housing 10 is preferably comprised of a non-corrosivemetal but may also be fabricated from a suitable plastic material.Housing 10 defines an inlet connection 12 and a plurality of outletconnections 14. As may be seen by reference to FIGS. 2 and 2A, in oneembodiment the valve of FIG. 1 was provided with six horizontal outletconnections 14. The outlet connections 14 may also be configured forvertical discharge or at some intermediate angle suitable for aparticular application.

Housing 10 is provided with a central bore which is open at the top ofthe housing with the valve oriented as shown in FIG. 1; the valvecentral bore in part providing communication between inlet conection 12and a selected discharge connection or connections 14. In the embodimentof FIG. 1 the central bore of housing 10 is capped by a diaphragmhousing indicated generally at 16. The purpose of the diaphragm housingand the components supported thereby will be described in detail below.It is believed that it will be sufficient for the present to note thatdiaphragm housing 16 may be replaced by a cap and that the diaphragmhousing or cap is secured to valve body 10 by means of a plurality ofbolts; the bolts having been omitted from the drawing in the interest offacilitating understanding of the invention.

An inlet housing member, indicated generally at 18, is positioned withinthe central bore of housing as shown. Member 18 is provided with anoutwardly extending flange which is sandwiched between housing member 10and cap housing 16; an O-ring seal 20 being provided to prevent externalleakage between members 18 and 20. A second seal ring 22 preventsleakage be tween the inlet connector 12 and the interior of the valvehousing past member 18. Member 18 in part defines, for the purposes tobe described below, a plurality of fluid flow paths. Theprincipal flowpath is directly between inlet connector 12 and the interior of housing10 downstream of member 18 via an opening or inlet port 24. Opening orport 24 is commensurate in diameter with inlet connector 12 and isdefined by an upwardly and inwardly extending portion 26 of member 18.Portion 26 of member 18 cooperates, in the manner to be described below,with a pintle assembly indicated generally at 28. Member 18 partlydefines further fluid flow paths 29 and 31) which communicate with theinterior of diaphragm housing 16 for the purposes to be described below.

The pintle assembly 28 includes a pintle 31 and a pintle cap 32 and maybe comprised of a light-weight noncorrosive metal alloy or moldedplastic. The pintle assembly 28 is mounted, in the manner to bedescribed below, on the valve rotor assembly, indicated generally at 34,and is capable of limited reciprocal motion with respect to the rotor.The pintle assembly is biased away from the rotor assembly and towardthe inlet port 24 by spring 36 and is prevented from becoming disengagedfrom an upwardly extending portion 37 of the rotor by a retaining ring38.

The rotor assembly 34 includes, in addition to aforementioned spring 36and extension 37, a valve member which selectively cooperates with allbut a preselected number, typically one, of discharge ports formed inhousing 10. In FIG. 1 a pair of discharge ports 40 and 40' are shown;port 40 being closed by the rotor valve member 42 and port 40' beingopen to permit flow through the valve and out of the outlet connector 14associated with the open discharge port. A pair of alternate dischargeport arrangements are shown in FIGS. 2 and 2A. The discharge ports aredefined by housing 10 and are formed with rounded valve seat definingportions which are slightly raised with respect to the direction ofmotion of the cooperating valve member 42. The valve member 42 iscovered by a suitable resilient material 44 whereby leakage about thevalve member through the closed ports is prevented; Member 44 may becomprised of a suitable elastomer material and is provided with aplurality of integral ribs 46 for the purposes to be described below. Inone embodiment the valve member portion 42 of the rotor assembly 34 hasa frustoconical shape; this shape enhancing the reliability of the valveas will be described below. It will be obvious to those skilled in theart that a flat rotor could be employed in the present invention at theexpense of requiring a larger valve housing. Similarly, a hemisphericalrotor configuration is possible.

As discussed above, the pintle assembly 28 is mounted on an extension 37of the rotor. In the disclosed embodiment extension 37 is integral withvalve member 42 and includes a solid upper portion and two coaxialhollow portions of different diameter. The junction between the hollowportions of extension 37 defines a shoulder for grounding a first end ofthe spring 36; the spring being coaxial with the intermediate diameterportion of extension 37. An upper cam 50 is mounted in and affixed tothe lower or larger diameter portion of valve member extension 37; uppercam 50 thus rotating with the rotor assembly 34 when the valve issequenced in the manner to be described below. A lower cam 52 is alsomounted within and rotates with extension 37; the earns 50 and 52 beingmaintained in position by means of a splined arrangement in combinationwith extension 37 and a cam retaining ring 54. The configuration ofearns 50 and 52 may be seen from FIG. 3 which represents the cams asthey would appear if flattened out linearly. It will be noted that cam52 is provided with an entrance slot 56 whereby a cam follower may beinserted into the cam assembly. The cam members function as both cam andbearing and thus are preferably made of a long wearing material with alow coefficient of friction. Thus, by way of example only, when aplastic rotor is employed the cams may be fabricated from cast or moldednylon sized to compensate for the effects of water absorption. When ametal rotor is employed the cams may, also by way of example only, beformed of impregnated bronze.

The combined pintle-rotor assemblies are mounted coaxially of a centerpost 58. Post 58 is in turn coaxial with the valve housing 10 and iskeyed therein as shown. Center post 58 is of tubular construction andhas integral therewith an outwardly extending cam follower 60. Thecenter post may either be cast or a section of tubing with follower 60and the locating key brazed thereto can be employed. The stationary camfollower 60 cooperates with the cams 52 and 54 in the manner to bedescribed below to index a valve. A re turn spring 62 is positionedwithin center post 58 and a guide pin 64 is supported by spring 62.Guide pin 64 has a hemispherical head, to reduce rotational friction,which contacts the top interior surface of the intermediate diameterportion of extension 37 thereby urging the rotor-pintle assembliesupwardly toward the inlet port 24.

Before continuing with a description of the FIG. 1 embodiment, theoperation of those portions of the sequencing valve already describedwill be discussed. The valve is shown in FIG. 1 in the seated or flowingposition. That is, as shown in FIG. 1 the valve has been indexed to opendischarge port 40 and the rotor assembly is at the bottom of its stroke.FIG. 1 thus depicts the full flow condition. If flow through the inletport 24 is momentarily interrupted the combined action of springs 62 and36 will cause the pintle and rotor assemblies to move upwardly. Duringthe upward movement the cam follower 60 will contact the lower cam 52.As will be obvious from FIG. 3, the rotor will be partly indexed in theclockwise direction toward its next position during the upward stroke.When the valve assumes its no flow condition the pintle 31 willeffectively block the inlet port 24. When pressure is again applied atinlet port 24 the pintle assembly will be forced downwardly and theforce generated by the application of fluid pressure to the pintle willbe transmitted from the pintle to the rotor via spring 36 therebycausing the rotor to move downwardly. The downward motion of the rotorwill, due to the combined action of the cam follower 60 and associatedcams 50 and 52, complete the rotation of the valve member 42 to its newposition.

It is to be particularly noted that the contour of the lower indexingcam 52 insures, during the last portion of the downward stroke, axialmotion only of the rotor thereby preventing scuffing of the sealingsurface on the valve seats defined by the discharge ports 40.

To summarize the preceding operational description, as flow enters theinlet port 24 the spring loaded pintle assembly 28 provides apredetermined restriction. The clearance between pintle 28 and the inletport 24 can be relatively large in the interest of insuringcontamination insensitivty while still presenting a small leakage areathat will establish the minimum flow rate necessary to create thepressure differential required to cycle the valve. The resultingpressure differential developed across the pintle 31 provides a forcewhich is a combined function of the pintle and rotor spring rates. Thisforce is transmitted to the rotor assembly 34 by the lower end of thepintle spring 36 and is of sufficient magnitude to force the rotor tothe bottom of its travel against the force of the rotor return spring62. A particularly significant feature of the invention is the fact thatthe pintle is free to over-travel relative to the rotor as a function offlow with the rotor seated at the bottom of its travel as shown inFIG. 1. A low pressure loss is thus maintained across the pintleassembly over a wide flow range. Also, separation of the cycling andsealing elements permits the valve to cycle consistently at low flowrates while having an acceptable pressure loss at high flow rates.

At the bottom of the stroke of the rotor all the valve outlets exceptthose selected by the rotor configuration are sealed by contact of theflexible member 44 with the rounded edges which define the valve seatsabout the discharge ports 40. The interior of the extension 37 of therotor, which includes the cams and cam follower, is also sealed from theflow stream by the flexible lower surface on the rotor and the indexingelements are accordingly isolated from exposure to any contaminateswhich may be carried by the fluid being distributed. Additionally, theconical rotor configuration directs any contaminates entering the valveto the open discharge port thus providing a self-cleaning feature. Theself-cleaning feature in combination with isolation of the indexingelements from the main stream results in virtual elimination of jammingas a result of exposure to fluid-born contaminates. The conical rotoralso allows a smooth transition from the valve exit port 40 to thedischarge fitting 14.

The raised ribs 46 on the flexible member 44 insure that the valve willbe unseated when flow is interrupted even though there may be a residualstatic pressure in the valve housing due to the presence of an outletcircuit with an average elevation higher than that of the valve. Theribs 46 will raise the rotor a predetermined height off the dischargehousing thereby allowing drainage of the elevated circuit through theremaining outlets. This drainage will lower the static pressure leveland allow the rotor return spring 62 to move the rotor upwardly. Aspreviously explained, as the rotor is pushed to the top of its stroke itis rotated by the lower cam 52 acting against the stationary camfollower 60 to provide partial indexing to the next port position.

It is particularly noteworthy that the use of an independent variablerestriction, as defined by the pintle assembly 28, allows the use oflarge, low pressure loss outlet ports. Referring again to FIGS. 2 and2A, segmented annular discharge ports are used to minimize the valvesize and leave little unused space for contamination build-up. A numberof different outlet port configurations can, of course, be utilized andthe two different configurations depicted in FIGS. 2 and 2A arerepresentative only. The earns 50 and 52 may, of course, be changed tochange the number of active outlets. Changing of cams, and any othermaintenance procedure that may be necessary, is easily accomplished byremoving the cap or solenoid housing 16 thereby permitting access to theinterior of the housing 10. With the cap removed, the inlet housing 18may be lifted out, the pintle-rotor assembly indexed so as to align camfollower 60 with the entrance slot 56 in lower cam 52 and the entireinterior assembly with the exception of the center post 58 lifted out ofthe housing.

Returning to a discussion of FIG. 1, should it be desired to use thesequencing valve of the present invention with a city-fed water system;i.e., with a system which does not provide for convenient shut-off ofthe supply of fluid to the valve in order to command cycling; a solenoidoperated shut-off valve may be incorporated in the sequencing valveassembly. To this end, the valve housing cap may be replaced by asolenoid valve housing as shown. Solenoid housing 16 will include asolenoid 80, a normally closed solenoid operated valve member 86 and aspring loaded diaphragm 82. Flow is allowed to enter the diaphragmcavity; i.e., the space between the upper side of diaphragm 82 and theinside top of housing 16, via aforementioned passage 29, a filter 84 andan orifice assembly 102; the orifice assembly incorporating fluidicresistors in the interest of contamination insensitivity. The filterkeeps contamination out of the housing 16 thereby insuring properseating of the solenoid operated valve element or solenoid pin 86.

As may be seen from FIG. 1, the diaphragm 82 is sandwiched between inlethousing 18 and diaphragm housing 16 and has an integral O-ring seal 88to insure against leakage. Diaphragm 82 may be comprised of a suitableelastomer material and includes a central portion of increased thicknesswhich functions as a valve element; the diaphragm 82 cooperating withthe portion 26 of inlet housing 18 which defines inlet port 24.Diaphragm 82 is loaded toward inlet port 24 by spring 90 and issupported by washers 92 and 94. A bleed plug 96 is provided to permitremoval of any air which may become trapped above diaphragm 82. Accessto filter 84 for cleaning is achieved by a filter access plug 98; plug98 including a recess which houses a spring 100. The end of spring 100displaced from plug 98 contacts orifice assembly 102 which, in turn, ispositioned directly downstream of filter 84 and holds the filter inplace. The filter, of course, also prevents contamination of the orificein assembly 102.

In operation, flow is allowed to enter the diaphragm cavity throughfilter 84 and the orifice assembly 102. The orifice assembly providesmeans for dampening the response of the diaphragm in the interest ofpreventing water hammer and limits the flow rate into the diaphragmcavity. Flow is allowed to leave the diaphragm cavity through thesolenoid cavity in which the solenoid valve element 86 is disposed. Thesolenoid cavity is ported to the main chamber of the sequencing valvedownstream of pintle assembly 28 via passage 30. The flow path for fluidexiting the diaphragm cavity offers less resistance then is presented toflow entering the cavity through orifice assembly 102.

When the solenoid 80 is energized the solenoid pin or valve element 86retracts to the position shown in FIG. 1 thereby allowing fluid to flowout of the diaphragm cavity thus lowering the diaphragm cavity pressure.This action will cause a pressure differential to be developed acrossthe diaphragm and the diaphragm will move upwardly against spring 90.When solenoid 80 is deenergized the pin or valve element 86 extends andseals the solenoid chamber by contacting the valve seat defined byinsert 104 thus closing flow path 30. The closing of the solenoid valvewill permit the pressure differential across the diaphragm 82 to decayand the diaphragm will move downwardly under the influence of spring 90.At the lower limit of its spring induced movement the valve elementdefining portion of the diaphragm will contact the upper end of inlethousing portion 26 thereby interrupting flow from inlet connector 12past the pintle assembly 28 via inlet port 24. The valve will thus cyclein the manner described above.

Referring now to FIG. 4, a second embodiment of a solenoid actuated,flow operated sequencing valve in accordance with the present inventionis disclosed. The valve of FIG. 4 differs from the FIG. I embodiment bymeans of the employment of a piston-diaphragm assembly to unseat thevalve element rather than interrupting flow and allowing a spring tounseat the valve element. The embodiment of FIG. 4, accordingly, hasapplication in city water-fed systems and/or in situations wherein thereare elevated outlet circuits which might delay cycling due to backpressure effects.

In the FIG. 4 embodiment a shoulder is formed on the interior surface ofhousing and an inlet port defining member 118' is mounted on thisshoulder by means of a snap ring 200. Also in the FIG. 4 embodiment, thepintle is in the form of a combined pistondiaphragm assembly including apintle portion 30 and a piston element 202. The piston element 202 isattached to a diaphragm 82 as shown. Diaphragm 82' is sandwiched betweenthe solenoid housing 16 and the main valve housing 10 so as to define apiston chamber 203. The piston-diaphragm assembly is mounted on andmoves with a piston rod 204 which has a longitudinal passagetherethrough; a snap ring 206 being em ployed to maintain thepositioning of the pistondiaphragm assembly with respect to the pistonrod. Motion of the piston rod with respect to a cylinder extension 208of diaphragmhousing 16 is guided by a piston bushing 210. The pintleportion of the piston is hollow as shown and provides a housing for therotor spring 212.

To briefly describe operation of the FIG. 4 embodiment, the first motionof the piston during cycling lifts the lower or pintle portion of thepiston-diaphragm assembly toward the inlet housing bore defined bymember 18'. The sequencing valve will be unseated just prior to thepintle reaching the minimum flow position. The controlling flow area forthe remainder of the valve stroke is thus set by the pintle/inlethousing clearance. This arrangement prevents a sudden flow increase whenthe valve element or rotor is unseated and a sudden fiow decrease whenthe valve is seated and thereby prevents water hammer when the valve iscycled by maintaining essentially constant flow during the cyclingprocedure.

Flow enters the piston chamber 203 through filter 84 and orificeassembly 102; orifice assembly incorporating fiuidic resistors in theinterest of contamination insensitivity. The venting of flow from thepiston chamber is controlled by means of the solenoid operated valveelement 86. When the solenoid is deenergized, and the solenoid valve pin86 extended, the piston chamber will be dead ended and the pressureinside the chamber will be the same as the supply pressure. Under theseconditions the pressure differential across the pintle portion of thepiston will cycle the piston downwardly against the top of center post58, which functions as a stop, to the position shown. The valve elementwill be seated prior to completion of the piston stroke through theaction of the spring loaded connection between the piston and valveelements as provided by spring 212, and pintle overtravel is thuspermitted in the interest of flow rate compensation.

When solenoid is energized and the pin or valve element 86 retracted,fluid is vented from the piston chamber via the solenoid 'valve chamber,the passage in piston rod 204 and the tubular center post 58. The centerpost 58 is provided with discharge ports 214 whereby the flow ventedfrom the piston chamber may be directed to distribution circuits whichare not currently flowing through flow passages 215 integral with rotorassembly 44. Since fiow into the piston chamber is restricted by orificeassembly 102, the pressure in the chamber will be reduced when thesolenoid valve is opened and the piston will accordingly travel to itsupper limit of travel as defined by stops 216. The upward motion of thepiston will, of course, partly cycle the valve and the cycle will becompleted in the manner described above when solenoid 80 is deenergizedthereby allowing the valve element 86 to interrupt the communicationbetween the piston chamber and the discharge path via the piston rod andcenter post.

As will now be obvious to those skilled in the art, the above describedvalve solves the problems associated with previous sequencing valveconcepts and offers cost and reliability advantages when compared to theprior art. The present invention will provide a progressive sequencingof the individual circuits in a flow system when the inlet flow iscycled or in response to an electrical signal applied to a pilotsolenoid valve. Thus, completely automatic operation is possibleemploying the present invention with a single station timer operatingthe pilot solenoid or a pump relay.

It is particularly significant that valves designed in accordance withthe present invention will operate reliably, with a low pressure loss,over a wide flow range. This capability allows one valve to fit avariety of applications or have application in an installation which mayhave a wide range 'of How rates in the individual circuits.Additionally, the unique design of the present invention permits thevalve to cycle without detrimental water hammer effects; this desirableresult being due to the action of the valve pintle which restricts flowduring cycling.

A principal design feature of the present invention is the utilizationof separate valve elements to generate the force required for cyclingand to provide the port sealing function. A supplementary, but alsoimportant, design feature resides in the ability of the force generatingelement to over-travel relative to the port sealing element as achievedthrough the use of resilient means for interconnecting the two elements.The force generating element can therefore provide adequate forces forcycling at low flow rates and yet over-travel after the rotor is seatedto maintain a low pressure loss at high flow rates. Since a pressuredrop across the port sealing element is not required for cycling, thevalve can incorporate large low pressure loss discharge ports 1 and alarge clearance between the port sealing and the valve housing in theinterest of contamination insensitivity.

While preferred embodiments have been shown and described, variousmodifications and substitutions may be made thereto without departingfrom the spirit and scope of the invention. Accordingly, it is to beunderstood that the present invention has been described by way ofillustration and not limitation.

What is claimed is: 1. A sequencing valve comprising: housing means,said housing means defining an inlet connection and a plurality ofoutlet ports displaced from said inlet connection, said housing meansfurther defining an internal bore whereby fluid communication may beestablished between said inlet connection and outlet ports; valve meansdisposed in said housing means bore, said valve means being reciprocaland rotatable and cooperating with said outlet ports to perform avalving function, said valve means having at least a first openingtherein whereby communication between at least one of said outlet portsand said valve means bore will be established at all times;

pressure responsive force generating means disposed in said housingmeans bore upstream of said valve means, said force generating meansbeing coupled to said valve means for causing reciprocation thereof inresponse to fluid pressure variations in said housing means bore, saidpressure responsive force generating means being movable relative tosaid valve means in response to flow through the valve to form avariable restriction; and

cam means disposed in said housing means for causing stepwise rotationof said valve means in response to reciprocation thereof produced bypressure induced movements of said force generating means.

2. The sequencing valve of claim 1 wherein said pressure responsiveforce generating means is resiliently coupled to said valve means.

3. The sequencing valve of claim 1 further comprising:

means defining an inlet port, said inlet port defining means beingpositioned in said valve housing means bore and cooperating with saidforce generating means to define a flow path between said inletconnector and outlet ports, movements of said force generating meanscausing variation of the area of said flow path commensurate withapplied pressure.

4. The sequencing valve of claim 2 further comprising:

means defining an inlet port, said inlet port defining means beingpositioned in said valve housing means bore and cooperating with saidvariable restriction defining means, movements of said variablerestriction defining means causing variation of the area of the flowpath between said housing means inlet connection and outlet ports.

5. The apparatus of claim 1 wherein said pressure responsive forcegenerating means comprises:

pintle means; and

spring means resiliently coupling said pintle means to said valve means.

6. The apparatus of claim 4 wherein said variable restriction definingmeans comprises:

pintle means; and

spring means resiliently coupling said pintle means to said valve means.

7. The sequencing valve of claim 6 wherein said valve means comprises:

a valve member which cooperates with said housing means outlet ports toselectively close at least one of said outlet ports; and

spring means biasing said valve member away from said outlet ports.

8. The sequencing valve of claim 7 wherein said valve member presents afrustoconical surface to fluid flowing through the sequencing valve,said frustoconical surface being interrupted at each opening in saidvalve member.

9. The sequencing valve of claim 6 wherein said valve means comprises:

a valve member which cooperates with said housing means outlet ports toselectively close at least one of said outlet ports.

10. The sequencing valve of claim 9 wherein said cam means comprises:

cooperating upper and lower cams affixed to and movable with said valvemember; and

a fixed position cam follower mounted from the interior of said housingmeans.

11. The sequencing valve of claim 10 wherein said valve member has ahollow center portion extending coaxially of the housing means bore andwherein said cooperating upper and lower cams are mounted within saidhollow valve member center portion whereby said cam means are isolatedfrom fluid passing through the valve.

12. The sequencing valve of claim 11 wherein said cam followercomprises:

a tubular member affixed to said housing means and being coaxial withsaid valve member hollow center portion, said tubular member beingdisposed within said valve member center portion; and

a cam follower projection extending outwardly from said tubular member.

13. The sequencing valve of claim 12 wherein said valve means furthercomprises:

spring means biasing said valve member away from said outlet ports, saidbiasing spring means being disposed within said tubular member.

14. The sequencing valve of claim 4 further comprising:

control valve means, said control valve means being remotely operable togenerate pressure pulses which control movement of said pressureresponsive force generating means in the downstream direction.

15. The sequencing valve of claim 14 wherein said control valve meanscomprises:

diaphragm means disposed in said housing means bore, said diaphragmmeans defining a diaphragm chamber upstream of said inlet port definingmeans;

means providing communication between the interior of said diaphragmchamber and said housing means inlet connection;

means for selectively controlling the venting of said diaphragm chamberto generate a pressure differential across said diaphragm means wherebysaid diaphragm means will move in a first direction; and

v. means coupling movements of said diaphragm means a p lug membersupported by said diaphragm m ns and cooperating with said inlet p ortdefinin g means for interrupting the flow of fluid through said inletport whereby the pressure differential across said forcegenerating meansis removed.

171 The seqtrehah'gvar've araam triinhei com prising: diaphragm meansdisposed in said housing means,

said diaphragm means defining a disphragm chamber upstream of said inletport defining means;

means providing communication between the interior of said diaphragmchamber and said housing means inlet connection;

means for selectively controlling the venting of said diaphragm chamberto generate a pressure differential across said diaphragm means wherebysaid diaphragm means will move in the upstream direction; and

means mechanically connecting said diaphragm means to said pressureresponsive force generating means, down stream movements of saidpressure responsive force generating means being responsive to flowthrough the valve when said disphragm chamber is unvented.

1. A sequencing valve comprising: housing means, said housing meansdefining an inlet connection and a plurality of outlet ports displacedfrom said inlet connection, said housing means further defining aninternal bore whereby fluid communication may be established betweensaid inlet connection and outlet ports; valve means disposed in saidhousing means bore, said valve means being reciprocal and rotatable andcooperating with said outlet ports to perform a valving function, saidvalve means having at least a first opening therein wherebycommunication between at least one of said outlet ports and said valvemeans bore will be established at all times; pressure responsive forcegenerating means disposed in said housing means bore upstream of saidvalve means, said force generating means being coupled to said valvemeans for causing reciprocation thereof in response to fluid pressurevariations in said housing means bore, said pressure responsive forcegenerating means being movable relative to said valve means in responseto flow through the valve to form a variable restriction; and cam meansdisposed in said housing means for causing stepwise rotation of saidvalve means in response to reciprocation thereof produced by pressureinduced movements of said force generating means.
 2. The sequencingvalve of claim 1 wherein said pressure responsive force generating meansis resiliently coupled to said valve means.
 3. The sequencing valve ofclaim 1 further comprising: means defining an inlet port, said inletport defining means being positioned in said valve housing means boreand cooperating with said force generating means to define a flow pathbetween said inlet connector and outlet ports, movements of said forcegenerating means causing variation of the area of said flow pathcommensurate with applied pressure.
 4. The sequencing valve of claim 2further comprising: means defining an inlet port, said inlet portdefining means being positioned in said valve housing means bore andcooperating with said variable restriction defining means, movements ofsaid variable restriction defining means causing variation of the areaof the flow path between said housing means inlet connection and outletports.
 5. The apparatus of claim 1 wherein said pressure responsiveforce generating means comprises: pintle means; and spring meansresiliently coupling said pintle means to said valve means.
 6. Theapparatus of claim 4 wherein said variable restriction defining meanscomprises: pintle means; and spring means resiliently coupling saidpintle means to said valve means.
 7. The sequencing valve of claim 6wherein said valve means comprises: a valve member which cooperates withsaid housing means outlet ports to selectively close at least one ofsaid outlet ports; and spring means biasing said valve member away fromsaid outlet ports.
 8. The sequencing valve of claim 7 wherein said valvemember presents a frustoconical surface to fluid flowing through thesequencing valve, said frustoconical surface being interrupted at eachopening in said valve member.
 9. The sequencing valve of claim 6 whereinsaid valve means comprises: a valve member which cooperates with saidhousing means outlet ports to selectively close at least one of saidoutlet ports.
 10. The sequencing valve of claim 9 wherein said cam meanscomprises: cooperating upper and lower cams affixed to and movable withsaid valve member; and a fixed position cam follower mounted from theinterior of said hoUsing means.
 11. The sequencing valve of claim 10wherein said valve member has a hollow center portion extendingcoaxially of the housing means bore and wherein said cooperating upperand lower cams are mounted within said hollow valve member centerportion whereby said cam means are isolated from fluid passing throughthe valve.
 12. The sequencing valve of claim 11 wherein said camfollower comprises: a tubular member affixed to said housing means andbeing coaxial with said valve member hollow center portion, said tubularmember being disposed within said valve member center portion; and a camfollower projection extending outwardly from said tubular member. 13.The sequencing valve of claim 12 wherein said valve means furthercomprises: spring means biasing said valve member away from said outletports, said biasing spring means being disposed within said tubularmember.
 14. The sequencing valve of claim 4 further comprising: controlvalve means, said control valve means being remotely operable togenerate pressure pulses which control movement of said pressureresponsive force generating means in the downstream direction.
 15. Thesequencing valve of claim 14 wherein said control valve means comprises:diaphragm means disposed in said housing means bore, said diaphragmmeans defining a diaphragm chamber upstream of said inlet port definingmeans; means providing communication between the interior of saiddiaphragm chamber and said housing means inlet connection; means forselectively controlling the venting of said diaphragm chamber togenerate a pressure differential across said diaphragm means wherebysaid diaphragm means will move in a first direction; and means couplingmovements of said diaphragm means to said pressure responsive forcegenerating means.
 16. The sequencing valve of claim 15 wherein saidcoupling means comprises: a plug member supported by said diaphragmmeans and cooperating with said inlet port defining means forinterrupting the flow of fluid through said inlet port whereby thepressure differential across said force generating means is removed. 17.The sequencing valve of claim 4 further comprising: diaphragm meansdisposed in said housing means, said diaphragm means defining adiaphragm chamber upstream of said inlet port defining means; meansproviding communication between the interior of said diaphragm chamberand said housing means inlet connection; means for selectivelycontrolling the venting of said diaphragm chamber to generate a pressuredifferential across said diaphragm means whereby said diaphragm meanswill move in the upstream direction; and means mechanically connectingsaid diaphragm means to said pressure responsive force generating means,down stream movements of said pressure responsive force generating meansbeing responsive to flow through the valve when said diaphragm chamberis unvented.